求教一道principle的逻辑题

bouncebill

Proposals for extending the United States school year to bring it more in line with its European and Japanese counterparts are often met with the objection that curtailing the school's three-month summer vacation would violate an established United States tradition dating from the nineteenth century. However, this objection misses its mark. True, in the nineteenth century, the majority of schools closed for three months every summer, but only because they were in rural areas where successful harvests depended on children labor. If any policy could be justified by those appears to tradition. It would be the policy of determining the length of the school year according to the needs of the economy.

25. Which one of the following principles, if accepted, would provide the strongest justification for the conclusion?

(A) That a given social policy has traditionally been in force justifies maintaining that policy only if doing so does not conflict with more pressing social needs.

(B) Appeals to us own traditions cannot excuse a country from the obligation to bring its practices in line with the legitimate expectations of the rest of the world.

(C) Because appeals to tradition often serve to mask the real interests the real interests at issue, such appeals should be disregarded.

(D) Traditional principles should be discarded when they no longer serve the needs of the economy.

(E) The actual tradition embodied in a given practice can be accurately identified only by reference to the reasons that originally prompted that practice.

这道题这两句话If any policy could be justified by those appears to tradition. it would be the policy of determining the length of the school year according to the needs to the economy.如果是if any policy could justify traditions,我就明白了,因为如果是这样那逻辑就是,首先说proposal:a new policy,然后说objection because tradition,then objection miss its mark, then tradition could be justified by any policy,it would be the ....needs of the economy.
但,他这样说实在是无法理解啊!!!逻辑太差,不懂他在说些什么
恳求帮助,十分感谢!!!!

cathycathyhan

选D。
D是最后一句话的逆否命题。If any policy could be justified by those appears to tradition. it would be the policy of determining the length of the school year according to the needs to the economy
就是来衡量这些政策根据看似的传统规矩，那么这些政策的决定学年的长短要根据经济的需求，就是传统规矩引导出经济需求相一致。D说，当传统规矩不符合经济需求，就要放弃。
A social needs，没有说
B  legitimate expectations 也不对
C mask the real interests the real interests at issue也不对
E 说传统的适用性要和这个传统的出处相一致，文章说传统和要经济需要一致，和文中意思相悖。所以也不对。

bouncebill

选D。
D是最后一句话的逆否命题。If any policy could be justified by those appears to tradition. it would be the policy of determining the length of the school year according to the needs to the economy
就是来衡量这些政策根据看似的传统规矩，那么这些政策的决定学年的长短要根据经济的需求，就是传统规矩引导出经济需求相一致。D说，当传统规矩不符合经济需求，就要放弃。
A social needs，没有说
B  legitimate expectations 也不对
C mask the real interests the real interests at issue也不对
E 说传统的适用性要和这个传统的出处相一致，文章说传统和要经济需要一致，和文中意思相悖。所以也不对。

-- by 会员 cathycathyhan (2011/9/10 8:16:54)

但是正确答案好像是E啊?!

日落归田园

应该选择E
总结原文，原文的逻辑如下：
要延长学年——这样会打破传统——传统有其特定背景——上文”传统“不成立——这里唯一行得通的传统就是”根据背景制定政策”

文中所提“经济”其实只是“传统背景“的一个体现
传统背景即E中所说”reasons originally prompted that practice"

cathycathyhan

选D。
D是最后一句话的逆否命题。If any policy could be justified by those appears to tradition. it would be the policy of determining the length of the school year according to the needs to the economy
就是来衡量这些政策根据看似的传统规矩，那么这些政策的决定学年的长短要根据经济的需求，就是传统规矩引导出经济需求相一致。D说，当传统规矩不符合经济需求，就要放弃。
A social needs，没有说
B  legitimate expectations 也不对
C mask the real interests the real interests at issue也不对
E 说传统的适用性要和这个传统的出处相一致，文章说传统和要经济需要一致，和文中意思相悖。所以也不对。

-- by 会员 cathycathyhan (2011/9/10 8:16:54)

但是正确答案好像是E啊?!

-- by 会员 bouncebill (2011/9/10 10:27:25)

后来我仔细看了看，D有个致命的错误是，原文中If any policy could be justified by those appears to tradition. It would be the policy of determining the length of the school year according to the needs of the economy.
这句话你仔细看文章中用了一个could be, would be的事态，could be 和would be 这里用的是虚拟语气，而不是肯定语气，如果选D，必须改成If any policy is justified by those appears to tradition. It will be  the policy of determining the length of the school year according to the needs of the economy.
而D用的是肯定语气，when they no longer serve for 这个是肯定语气。所以语气错了，所以选D错了。
而E非常生涩的语句，但是E用的是can，语气和原文的推理语气一样。所以，E是正确答案。有时候LSAT会出现2个非常相似的答案，但是往往错的是在语气或者时态上不符合，对的就是语气和时态是一致的，这个也是逻辑题目考查的一个范围。